Catalyst for converting synthesis gas to high octane predominantly olefinic naphtha

ABSTRACT

An improved catalyst composition is disclosed for converting synthesis gas to hydrocarbon mixtures. The catalyst comprises an iron-containing, Fischer-Tropsch catalyst and a crystalline zeolite having a silica-to-alumina ratio of greater than 200 (including zeolites containing essentially no alumina) and an (R 2  O+M 2  / n  O):SiO 2  rate of less than 1.1:1 where M is a metal other than a metal of Group IIIA, n is the valence of said metal, and R is an alkyl ammonium radical, said organosilicate being characterized by a specified x-ray diffraction pattern.

This application is a continuation-in-part of our copending applicationSer. No. 076,027, filed Sept. 17, 1979, now abandoned which is acontinuation of application Ser. No. 926,987, filed July 21, 1979, nowU.S. Pat. No. 4,172,843.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is concerned with an improved process for convertingsynthesis gas, i.e., mixtures of gaseous carbon oxides with hydrogen orhydrogen donors, to hydrocarbon mixtures. This invention is furtherconcerned with the catalyst composition which can be utilized ineffecting this conversion.

2. Description of the Prior Art

Processes for the conversion of coal and other hydrocarbons such asnatural gas to a gaseous mixture consisting essentially of hydrogen andcarbon monoxide and/or dioxide are well known. Those of major importancedepend either on the partial combustion of the fuel with anoxygen-containing gas or on the high temperature reaction of the fuelwith steam, or on a combination of these two reactions. An excellentsummary of the art of gas manufacture, including synthesis gas, fromsolid and liquid fuels, is given in Encyclopedia of Chemical Technology,Edited by Kirk-Othmer, Second Edition, Volume 10, pages 353-433 (1966),Interscience Publishers, New York, New York.

It is also well known that synthesis gas will undergo conversion toreduction products of carbon monoxide, such as hydrocarbons, at fromabout 300° F. to about 850° F., under from about one to one thousandatmospheres pressure, over a fairly wide variety of catalysts. TheFischer-Tropsch process, for example, which has been most extensivelystudied, produces a range of liquid hydrocarbons, a portion of whichhave been used as low octane gasoline. Catalysts that have been studiedfor this and related processes include those based on iron, cobalt,nickel, ruthenium, thorium, rhodium and osmium, or their oxides.

The conversion of synthesis gas into valuable products can be greatlyenhanced by employing a special type of crystalline aluminosilicatezeolite exemplified by ZSM-5 or ZSM-11 in admixture with a conventionalFischer-Tropsch catalyst. Thus, for example, in copending applicationSer. No. 463,711, filed Apr. 24, 1974, abandoned, but parent to U.S.Pat. No. 4,086,262, issued Apr. 25, 1978, and a parent to U.S. Pat. No.4,096,163, issued June 20, 1978 there is disclosed a process for theconversion of syngas by passing the same at elevated temperature over acatalyst which comprises an intimate mixture of a Fischer-Tropschcomponent and a special type of zeolite such as ZSM-5. Said copendingapplication points out that the products produced are hydrocarbonmixtures which are useful in the manufacture of heating oil, high octanegasoline, aromatic compounds and chemical intermediates.

As can well be appreciated, the patent and technical literature relatingto the Fischer-Tropsch process, is, indeed, extensive and the variouscatalysts reported in the prior art have been used by themselves as wellas in admixture with catalytically inactive supports such as kieselguhr.Although the reasons for using catalytically inactive supports havevaried, nevertheless, it would appear that one reason for using the samewas that it resulted in increased surface area of the Fischer-Tropschcomponent upon which it was deposited or admixed and that it also aidedin controlling the heat requirements of the overall exothermicreactions.

It is also known in the art to admix a Fischer-Tropsch component with amaterial, such as silica alumina which is known to be catalyticallyactive for the conversion of hydrocarbons.

U.S. Pat. No. 2,637,739 discloses a Fischer-Tropsch process involvingthe conversion of syngas by passing the same over a Fischer-Tropschcatalyst in admixture with silica alumina.

U.S. Pat. No. 3,894,102 is directed towards a two-stage process for theconversion of syngas wherein the first stage a methanol synthesiscatalyst is admixed with an acidic dehydrogenation catalyst and theproduct thereof contacted with an HZSM-5 type aluminosilicate zeolite.

In copending application Ser. No. 793,015, filed May 2, 1977 nowabandoned, there is disclosed a method for producing an olefinicgasoline by contacting a syngas with a catalyst mixture comprising twocomponents, one being a cobalt containing Fischer-Tropsch component andthe other being a ZSM-5 type aluminosilicate zeolite wherein theactivity of the ZSM-5 type aluminosilicate zeolite is balanced with theactivity of the cobalt containing Fischer-Tropsch component. The productresulting from this type of conversion is an olefinic gasoline whereinthe olefins are predominantly branched (>50 percent) and internal due tothe action of the ZSM-5 type component.

In copending application Ser. No. 793,016, filed May 2, 1977 nowabandoned, but parent to U.S. Pat. No. 4,304,871 issued Dec. 8, 1981,there is disclosed a method for producing an olefinic gasoline bycontacting a syngas with a catalyst mixture comprising two components,one being an iron-containing Fischer-Tropsch component and the otherbeing a ZSM-5 type aluminosilicate zeolite wherein the activity of theZSM-5 type aluminosilicate zeolite is balanced with the iron-containingFischer-Tropsch component. The product resulting from this type ofconversion is an olefinic gasoline having a clear research octane numbergreater than 85 wherein the olefins are predominantly branched (>50percent) and internal due to the action of the ZSM-5 type of component.

Also copending is application Ser. No. 775,129, filed Mar. 7, 1977 nowU.S. Pat. No. 4,269,783 issued Mar. 7, 1977 which is concerned with theconversion of syngas over a catalyst comprising a Fischer-Tropschcomponent and an acidic cracking catalyst and is also directed towardsbalancing the activity of the acidic component with the Fischer-Tropschcatalyst. However, the product obtained from the process of saidcopending application is an olefinic product wherein the olefins havepredominantly internal (>50 percent) double bonds and the gasoline has aclear research octane number greater than 75. The solid acidic componentutilized in the process of this copending application is not a ZSM-5type zeolite, but rather it includes the use of an amorphous material,such as silica alumina, as well as the more conventional typecrystalline aluminosilicates, such as faujasite, erionite, mordenite,etc., that are capable of sorbing n-hexane.

U.S. Pat. No. 3,013,990 suggests a catalyst composition useful inprocesses including Fischer-Tropsch synthesis (see Column 10, lines71-74) which composition comprises a zeolite molecular sieve containinga substantial quantity of at least one material selected from the groupconsisting of Fe, Co, Ni, and oxides thereof in the internal adsorptionarea of the zeolite molecular sieve. At Column 1, lines 38-39, "zeoliticmolecular sieves" are defined as "metal aluminosilicates", and all thezeolites disclosed have a relatively high ratio of alumina:silica. Noneof the zeolites have the composition or characteristic x-ray powderdiffraction pattern of the silica zeolite component recited in thepresent claims. Moreover, the patent does not discuss the preparation ofgasoline-boiling-range hydrocarbons.

The ZSM-5 type crystalline zeolite component of the intimate catalystmixture recited in the present claims is disclosed in U.S. Pat. No.3,941,871. The uses suggested therein for the crystalline zeolitecatalyst are hydrocracking, catalytic cracking, reforming,hydroisomerization of normal paraffins, and olefin isomerization (Column5, line 54 to Column 6, line 22). No process is discussed for the directconversion of synthesis gas to gasoline-boiling-range products.

SUMMARY OF THE INVENTION

The novel process of this invention is an improved process forconverting syngas to more valuable hydrocarbons in that it employs aspecial catalyst comprising a crystalline zeolite having asilica-to-alumina ratio of greater than 200 and an (R₂ O+M₂ /_(n)O):SiO₂ ratio of less than 1.1:1 where M is a metal other than a metalof Group IIIA, n is the valence of said metal, and R is an alkylammonium radical, said zeolite being characterized by a special x-raydiffraction pattern. Although the crystalline zeolite has been describedas having a silica-to-alumina ratio of greater than 200:1, it will beunderstood that the zeolite may contain no alumina. A specificembodiment of this invention is directed towards the formation of a veryspecific product. The liquid product of this embodiment, like that ofcopending patent application Ser. Nos. 793,015 and 793,016, is ahigh-octane, predominantly-olefinic naphtha having a boiling range ofless than 400° F. at a 90 percent overhead which is defined as a C₅ +naphtha with an aromatic content of less than 15-20 weight percent, anolefin-plus-aromatics content exceeding 50 weight percent wherein >50percent of the olefins (based on total pentenes) have a branched chainstructure and an internally-positioned double bond, and the gasoline hasa clear research octane number greater than 85.

The present invention is further concerned with obtaining theabove-defined product in good yields and good selectivities from thestarting syngas material.

The present invention is still further concerned with a catalystcomposition comprising potassium-promoted iron intimately admixed with acrystalline zeolite which catalyst composition is useful for convertingsynthesis gas to olefinic gasoline.

Prior teachings regarding the conversion of synthesis gas to olefinicgasoline have been based on the use of potassium-deactivated ZSM-5catalysts as exemplified by copending application Ser. No. 793,015 andSer. No. 793,016 described supra. The discovery of the present inventionis that a desirable alternative to such processes is to employ acrystalline silicate as the zeolite component of azeolite/Fischer-Tropsch component catalyst composition for syngasconversion.

DETAILED DESCRIPTION OF THE INVENTION

The materials known to reduce carbon monoxide to oxygenated or olefinichydrocarbon products that have at least one carbon-to-carbon bond intheir structure include zinc, iron, cobalt, ruthenium, thorium, rhodium,and osmium. With the exception of ruthenium, all practicalart-recognized synthesis catalysts contain chemical and structuralpromoters. These promoters include copper, manganese, chromia, alumina,the alkaline earths, the rare earths, and alkali. Alkali, e.g., thecarbonates of Group IA of the Periodic Table, and especially potassium,is of particular importance for use as promoters with iron catalysts.Potassium-modified iron Fischer-Tropsch catalyst greatly reduces theconversion to methane. Supports such as kieselguhr sometimes actbeneficially.

The crystalline zeolite component of the catalyst arrangement issubstantially free of alumina, but may contain very minor amounts ofsuch oxide attributable primarily to the presence of aluminum impuritiesin the reactants and/or equipment employed. Thus, the molar ratio ofalumina to silica will be in the range of 0 to less than 0.005 mole ofAl₂ O₃ to more than 1 mole of SiO₂. Generally the latter may rangefrom >1 SiO₂ up to 500 or more. Broadly, the SiO₂ /Al₂ O₃ ratio isgreater than about 200/1. Preferably, the ratio is greater than about500/1 and, more preferably is about 1300/1 or more. Preparation of thecrystalline zeolite component is described in U.S. Pat. No. 3,941,871,the entire content of which is incorporated herein by reference.

That patent provides a family of crystalline zeolites which areessentially free of Group IIIA metals, i.e., aluminum and/or gallium.These zeolites have surprisingly been found to be characterized by anx-ray diffraction pattern characteristic of the ZSM-5 type crystallinealuminosilicates. The method described in U.S. Pat. No. 3,941,871 mayalso be used to prepare crystalline zeolites of the ZSM-11 type whichare essentially free of Group IIIA metals. Similar to the crystallinezeolites described in the '871 patent, these zeolites are characterizedby an x-ray diffraction pattern characteristic of the ZSM-11 typecrystalline aluminosilicates, which are described in U.S. Pat. No.3,709,979, the entire content of which is incorporated herein byreference. In addition to having these characteristic x-ray diffractionpatterns, the crystalline zeolites of the present invention can beidentified in their anhydrous state in terms of mole ratios of oxides asfollows:

(1) A SiO₂ :Al₂ O₃ ratio of greater than 200:1 and

(2) an (xR₂ O+(1-x)M₂ /_(n) O):SiO₂ ratio of less than 1.1:1

where M is a metal other than a metal of Group IIIA, n is the valence ofsaid metal, and R is an alkyl ammonium radical and x is greater than 0but not exceeding 1. Preferably R is a tetraalkyl ammonium radical, thealkyl groups of which contain 2-5 carbon atoms.

In the above composition, R₂ O and M₂ /_(n) O may be removed byreplacement with or conversion to other desired components which serveto enhance catalytic activity, stability and/or sorption or absorptioncharacteristics. It is particularly contemplated that R and/or M may beat least partially in the ammonium form as a result of ion exchange.

As above noted, the families of crystalline zeolites disclosed andclaimed herein have definite x-ray diffraction patterns. Such x-raydiffraction patterns, similar to those for the ZSM-5 and ZSM-11zeolites, show the following significant lines:

                  TABLE 1                                                         ______________________________________                                        ZSM-5 TYPE CRYSTALLINE ZEOLITE                                                Interplanar Spacing d(A):                                                                       Relative Intensity                                          ______________________________________                                        11.1       ±0.2    s                                                       10.0       ±0.2    s                                                       7.4        ±0.15   w                                                       7.1        ±0.15   w                                                       6.3        ±0.1    w                                                       6.04                                                                                     ±0.1    w                                                       5.97                                                                          5.56       ±0.1    w                                                       5.01       ±0.1    w                                                       4.60       ±0.08   w                                                       4.25       ±0.08   w                                                       3.85       ±0.07    vs                                                     3.71       ±0.05   s                                                       3.04       ±0.03   w                                                       2.99       ±0.02   w                                                       2.94       ±0.02   w                                                       ______________________________________                                    

                  TABLE 2                                                         ______________________________________                                        ZSM-11 TYPE CRYSTALLINE ZEOLITE                                               Interplanar Spacing d(A):                                                                       Relative Intensity                                          ______________________________________                                        11.2        ±0.2   m                                                       10.1        ±0.2   m                                                       6.73        ±0.2   w                                                       5.75        ±0.1   w                                                       5.61        ±0.1   w                                                       5.03        ±0.1   w                                                       4.62        ±0.1   w                                                       4.39        ±0.08  w                                                       3.86        ±0.07   vs                                                     3.73        ±0.07  m                                                       3.49        ±0.07  w                                                       (3.07.3.00) ±0.05  w                                                       2.01        ±0.02  w                                                       ______________________________________                                    

The parentheses around lines 3.07 and 3.00 in Table 2 indicate that theyare separate and distinct lines, but are often superimposed. The valueswere determined by standard techniques. The radiation was the K-alphadoublet of copper and a Geiger Counter Spectrometer with a strip chartpen recorder was used. The peak heights, I, and the positions as afunction of two times theta, where theta is the Bragg angle, were readfrom the spectrometer chart. From these, the relative intensities, 100I/I₀, where I₀ is the intensity of the strongest line or peak andd(obs.), the interplanar spacing in A, corresponding to the recordedlines were calculated. In Table I the relative intensities are given interms of the symbols s=strong, w=weak and vs=very strong.

The crystalline zeolites can be used either in the alkali metal form,e.g., the sodium form or other desired metal form, the ammonium form orthe hydrogen form. Preferably, one of the last two forms is employed.The cation content should in no case be so large as to substantiallyeliminate the activity of the zeolite for the catalysis being employedin the instant invention. For example, a completely sodium exchangedZSM-5 or ZSM-11 appears to be largely inactive for shape selectiveconversions required in the present invention.

The specific zeolites described, when prepared in the presence oforganic cations, are substantially inactive, possibly because thecrystalline free space is occupied by organic cations from the formingsolution. The zeolites as synthesized or after impregnation can bebeneficially converted to another form by thermal treatment. This can bedone by heating to a temperature in the range of 200° to 600° C. in anatmosphere such as air, nitrogen, etc. and at pressures ranging fromsubatmospheric to above-atmospheric for between 1 and 48 hours.Dehydration may also be performed at lower temperatures merely byplacing the zeolite in a vacuum, but a longer time is required to obtaina sufficient amount of dehydration.

The crystalline zeolites as synthesized can have the original componentsthereof replaced by a wide variety of others according to techniqueswell known in the art. Typical replacing components would includehydrogen, ammonium, alkyl ammonium and aryl ammonium and metals, otherthan metals of Group IIIA, including mixtures of the same. The hydrogenform may be prepared, for example, by substitution of original sodiumwith ammonium. The composition is then calcined at a temperature of,say, 1000° F., causing evolution of ammonia and retention of hydrogen inthe composition. Of the replacing ions, preference is accorded to metalsof Groups II, IV and VIII of the Periodic Table with the caveat thattrivalent and tetravalent forms of Group IV and VIII metals may not besuitable "replacing components."

The crystalline zeolites are then preferably washed with water and driedat a temperature ranging from 150° F. to about 600° F. and thereaftercalcined in air or other inert gas at temperatures ranging from 500° F.to 1500° F. for periods of time ranging from 1 to 48 hours or more.

Regardless of the synthesized form of the zeolite, the spatialarrangement of atoms which form the basic crystal lattices remainessentially unchanged by the described replacement of sodium or otheralkali metal or by the presence in the initial reaction mixture ofmetals in addition to sodium, as determined by an x-ray powderdiffraction pattern of the resulting zeolite. The x-ray diffractionpatterns of such products are essentially the same as those set forth inTable 1 or Table 2 above.

The crystalline zeolites prepared in accordance with the instantinvention are formed in a wide variety of particular sizes. Generally,the particles can be in the form of powder, a granule, or a moldedproduct such as an extrudate having a particle size sufficient to passthrough a 2 mesh (Tyler) screen and be maintained on a 400 mesh (Tyler)screen in cases where the catalyst is molded such as by extrusion. Thezeolite can be extruded before drying or dried or partially dried andthen extruded.

As has been previously set forth, a particular aspect of this inventionresides in the production of a particular product utilizing a catalystmixture comprised of an iron Fischer-Tropsch component and a crystallinezeolite component. The catalyst mixtures contemplated may be prepared invarious ways. The two components may be separately prepared in the formof catalyst particles such as pellets or extrudates, for example, andthen mixed in the required proportions. The particle size of theindividual component particles may be quite small, for example, fromabout 0.01 to about 300 microns, when intended for use in fluid bedoperation; or they may be as large as up to about 1/2 inch for fixed bedoperation. The two components may also be mixed as powders in desiredproportions and formed into pellets or extrudate, each pellet containingboth components in substantially the required proportions. Binders suchas clays may be added to the mixture. Alternatively, the component thathas catalytic activity for the reduction of carbon monoxide may beformed on the acidic crystalline zeolite component by conventional meanssuch as impregnation of that solid with salt solutions of the desiredmetals, followed by drying and calcination. Base exchange of the acidiccrystalline zeolite component also may be used in some selected cases toeffect the introduction of part or all of the carbon monoxide reductioncomponent. Other means for forming the intimate mixture may be used,such as: precipitation of the carbon monoxide reduction component in thepresence of the acidic crystalline zeolite, electrolytic deposition ofmetal on the zeolite, or deposition of metal from the vapor phase.Various combinations of the above preparative methods will be obvious tothose skilled in the art of catalyst preparation.

In copending application Ser. No. 729,938, filed Oct. 6, 1976 nowabandoned, but parent to U.S. Pat. No. 4,304,871 issued Dec. 8, 1981, itis demonstrated that for the production of aromatic gasoline fromsynthesis gas the iron catalyst component is preferaby retained in anarrangement wherein it is surrounded by a relatively large proportion ofcrystalline zeolite component. The same type of configuration ispreferred in this invention, particularly under fixed bed operatingconditions. The crystaline zeolite-containing component is so arrangedto statistically promote the sequential reaction mechanism of synthesisgas conversion to primarily olefin intermediates by the iron catalystfollowed by chain growth of the olefin intermediate with the modifiedzeolite catalyst component to form branched chain and internal olefinsin preference to aromatics and before the olefin intermediate has achance to contact additional particles of iron catalyst. Thus, theabundance of zeolite particles about the iron particle intercepts theolefin intermediate of iron catalyst conversion before the olefinintermediate can build up into long-chain linear wax molecules.Supporting evidence for the above-identified reaction sequence andcatalyst component arrangement promoting the scavenging function by thezeolite catalyst component is provided by related studies on propyleneor methanol conversion to form aromatics with a ZSM-5 crystallinealuminosilicate zeolite. The fact that the zeolite component provides ascavenging function when properly proportioned with respect to thecarbon monoxide reducing component is further supported by data obtainedwith the heterogeneous catalyst mixture after treatment of particularlythe zeolite component to substantially eliminate the aromatizingfunction.

The novel process of this invention is carried out at temperaturesranging from about 450° F. and more preferably at least 550° F. to about750° F. such that no more than about 30 weight percent of methane plusethane is formed. Gas hourly space velocities (GHSV) range from 500 to20,000 and more desirably from 1000 to 6000 based on fresh feed andtotal catalyst volume. Hydrogen to carbon oxides ratios can vary from0.5 to 6.0 and more preferably from 1.0 to 2.0. Pressures range from 50to 1000 psig and more preferably from 150 to 400 psig. The ratio of theFischer-Tropsch component to the acidic solid (zeolite plus binder) isnot narrowly critical and can range from 1.0 to a practical maximum of20 volumes of the acidic solid per volume of the Fischer-Tropschcomponent. A particularly desirable range is from 2 to 10 volumes ofacidic solid per volume of Fischer-Tropsch component.

Operating within the above referred-to parameters will result in aprocess wherein at least 50 percent of the carbon monoxide in the freshfeed is actually converted. Since theoretical conversions vary withsyngas composition, a preferred conversion range on the fresh feed is atleast 50 percent of the carbon monoxide and of the hydrogen based ontheoretical.

The following Examples 1-5 are limited primarily to one representativepressure, 200 psig; and a GHSV range of 1500 to 3400 based on activereagents, which is considerably higher than normally used for commercialfixed bed operation. These conditions are not, of course, optimum fordemonstrating temperature limits of process operability. Fresh feed GHSVof 500 and even less are recorded in Fischer-Tropsch process literature.Obviously, if the GHSV were reduced from 3500 to 500, the operatingtemperature could be reduced substantially below 500° F. before losingFeK and/or zeolite activity.

EXAMPLES 1-5

Syngas with a hydrogen to carbon monoxide ratio of 2 was contacted at a600° F. catalyst bed setting, a pressure of 200 psig and a gas hourspace velocity (GHSV) of 3200-3600 with various aluminosilicate andsilicate ZSM-5-type catalysts intimately mixed with Fe(K). In allExamples, the ZSM-5-type component was sized to 12-25 mesh and 1.6 cc ofthe sized ZSM-5-type component was mixed with 0.4 cc of 12-25 meshGirdler G-82 Fe(K). The runs were monitored and the products measuredand analyzed. Results are shown in Table 3 below. The ZSM-5-typecomponent of Examples 1, 2, 3, and 4 were bound with 35 weight percentCatapal alumina and extruded as 1/16" extrudates. The ZSM-5-typecomponent of Example 5 is the pure acid form of the silicate ZSM-5-typecomponent. Examples 1 and 2 are comparative examples showing syngasconversion over an Fe(K)/aluminosilicate ZSM-5-type component. Examples3-5 show syngas conversion according to the process of the presentinvention over an Fe(K)/silicate ZSM-5-type component.

Comparing Examples 1, 3, and 4, it may be seen that the main effect ofincreasing SiO₂ /Al₂ O₃ ratio is to decrease aromatic make.Aromatization is related to site density. Site strength appears to varyexponentially with SiO₂ /Al₂ O₃ ratio since a semilog plot of C₆ +aromatics produced in Examples 1, 3 and 4 as a function of SiO₂ /Al₂ O₃ratio is nearly a straight line.

The catalyst of Example 2 (70/1 SiO₂ /Al₂ O₃ ZSM-5 extrudate (35 percentbinder) poisoned with potassium) has performed well in separateparticle, fixed bed operation. However, attempts to put theK-deactivated 70/1 SiO₂ /Al₂ O₃ ZSM-5 into the same particle with <250μFe(K) have failed because of excessive methane formation. ComparingExamples 2 and 5, it will be noted that the 1600/1 pure SiO₂ crystallinezeolite differs only slightly from the K-deactivated, 70/1 SiO₂ /Al₂ O₃ZSM-5 and is a desirable alternative to the latter catalyst for syngasconversion.

                                      TABLE 3                                     __________________________________________________________________________                     Example                                                      ZSM-5-type              2                  5                                  Catalyst         1      K(0.95%)--                                                                           3     4     Pure SiO.sub.2                     Component        65% SiO.sub.2 --                                                                     SiO.sub.2 --Al.sub.2 O.sub.3                                                         65% SiO.sub.2                                                                       65% SiO.sub.2                                                                       crystalline                        Description      Al.sub.2 O.sub.3 ext.                                                                ext.   ext.  ext.  zeolite                            __________________________________________________________________________    SiO.sub.2 /Al.sub.2 O.sub.3                                                   ratio in ZSM-5-                                                               type component   70     70     500   1600  1600                               Run Time (Hrs.)  24     23     24    23.5  223/4                              Accum. Time                                                                   (Days)           2.0    1.8    1.8   1.8   1.7                                GHSV             3420   3215   3280  3375  3580                               WHSV             1.62   1.54   1.50  1.53  1.89                               Temp. (°F.), Ave.                                                                       618    620    619   621   626                                Hot Spot         628    628    624   629   636                                CO Conv. (wt. %) 95     97     96    97    94                                 H.sub.2 Conv. (wt. %)                                                                          54     59     53    54    45                                 Hydrocarbon Composition (wt. %)                                               C.sub.1          17     17     20    17    18                                 C.sub.2          4      6      7     6     8                                  C.sub.3          8      4      5     4     6                                  C.sub.4          18     11     12    12    14                                 C.sub.5          11     10     12    12    13                                 C.sub.6 +        42     52     44    49    41                                 Olefins (wt. % by C no.)                                                      C.sub.2          6      26     33    32    40                                 C.sub.3          7      45     28    46    53                                 C.sub.4          4      53     54    56    68                                 C.sub.5          3      57     57    63    74                                 C.sub.5 Olefin Dist. (wt. %)                                                  1- C.sub.5 ═ --     3      3     2     3                                  T + C.sub.2 C.sub.5 ═                                                                      6      18     20    18    19                                 MC.sub.4 ═   94     79     77    78    78                                 C.sub.6 + Aromatics                                                           (wt. %)          50     13     21    14    13                                 Liq. Prod. 90%                                                                B.P. (°F.)                                                                              402    350    358   360   356                                C.sub.5 + O.N. (R + O)                                                                         92.1   92.0   92.1  91.7  92.6                               __________________________________________________________________________

We claim:
 1. A catalyst composition comprising an iron-containingFischer-Tropsch component and a volume excess of a solid containing acrystalline zeolite, wherein the crystalline zeolite comprises a zeolitehaving a composition in its anhydrous state in terms of mole ratios ofoxides as follows:(a) an Al₂ O₃ :SiO₂ ratio within the range of from 0to less than 0.005 Al₂ O₃ to more than 1 SiO₂ and (b) an (xR₂ O+(1-x) M₂/_(n) O):SiO₂ ratio of less than 1.1:1where M is a metal other than ametal of Group IIIA, n is the valence of said metal, R istetraalkylammonium and x is a number greater than 0 but not exceeding 1,said zeolite having the x-ray diffraction lines set forth in Table 1 orTable 2 of the specification.
 2. The catalyst of claim 1 wherein M issodium or sodium in combination with tin, calcium, nickel or zinc. 3.The catalyst of claim 1 wherein the volume ratio of said solid to saidFischer-Tropsch component is between 1 and
 20. 4. The catalyst of claim3 wherein said volume ratio is between 2 and
 10. 5. The catalyst ofclaim 1 wherein the SiO₂ :Al₂ O₃ ratio of the crystalline zeolite isgreater than about 200:1.
 6. The catalyst of claim 1 wherein the SiO₂:Al₂ O₃ ratio of the crystalline zeolite is greater than 500:1.
 7. Thecatalyst of claim 1 wherein the SiO₂ :Al₂ O₃ ratio of the crystallinezeolite is greater than 1300:1.
 8. The catalyst of claim 1 wherein thecrystalline zeolite has been exchanged with ammonium ions.